The geological age and phytogeographical significance of some metamorphosed palynomorphs from the Omichidani Formation of Japan

Thermally altered and carbonised palynomorphs from the Omichidani Formation in the Tetori area of west-central Japan are poorly preserved but identifiable at the genus level. They include fern spores and gymnosperm pollen, and pollen of the angiosperm genera Aquilapollenites, Tschudypollis ("Proteacidites") and Wodehouseia. Pollen of other angiosperms is also present. The angiosperm pollen attests to the Maastrichtian age of the formation and the phytogeographical similarity of western North America and eastern Asia in Late Cretaceous time.